Hi Simon,
We do the dance because it’s how we always have and don’t know any other way, any better way. :) The usual explanation.
Isthere any place you can point to that demonstrates your technique?
Thanks!
P
--
Paul Ramsey
http://cleverelephant.ca/
http://postgis.net/
On Sunday, November 24, 2013 at 8:21 AM, Simon Riggs wrote:
> On 19 November 2013 23:08, Paul Ramsey <pramsey@cleverelephant.ca (mailto:pramsey@cleverelephant.ca)> wrote:
>
> > On the solution, I wasn't suggesting another void* slot, but rather a
> > slot that holds a hash table, so that an arbitrary number of things
> > can be stuffed in. Overkill, really, since in 99.9% of times only one
> > thing would be in there, and in the other 0.1% of times two things. In
> > our own GenericCacheCollection, we just statically allocate 16 slots.
>
>
>
> Why do you need to do this dance with fn_extra?
>
> It's possible to allocate a hash table in a Transaction-lifetime
> memory context on first call into a function then cache things there.
>
> --
> Simon Riggs http://www.2ndQuadrant.com/
> PostgreSQL Development, 24x7 Support, Training & Services